In the conventional technology pertaining to related art, the special advantage of Complementary Metal-Oxide-Semiconductor (CMOS) image sensors is characterized by “low power consumption” and “small volume”. Therefore, CMOS image sensors can be easily integrated into portable electronic products with special requirements. For example, CMOS image sensors can be easily integrated into portable electronic products with small integration space, such as smart phones, tablets or notebooks, etc.
However, the width of conventional CMOS image sensors still cannot be effectively shortened. Therefore, how the width of the conventional CMOS image sensor can be effectively shortened by making improvements to the structural design thereof has become an important issue in the industry.